What is one way that pathogens can cause disease in the body?

Pathogens can cause disease in the body by producing toxins or poisons. Many bacteria and some viruses secrete harmful substances that can damage host tissues, disrupt normal cellular functions, or provoke an inflammatory response, all of which can lead to illness. For example, certain strains of bacteria, such as Clostridium botulinum, produce neurotoxins that can cause paralysis, while others may produce enterotoxins that lead to gastrointestinal distress.

In contrast, the other options suggest beneficial effects or functions that pathogens do not typically fulfill. Improving immune response and aiding nutrient absorption are functions associated with healthy body processes rather than pathogenic activity. Preventing allergies refers to interactions that help maintain immune balance, which is not a role played by pathogens. By focusing on their ability to produce harmful substances, we can understand a significant mechanism through which pathogens contribute to disease.